This invention relates to the field of latching mechanisms and more particularly to automatic means for preventing the opening of an access door to the rotor chamber of an air driven centrifuge while the rotor is rotating.
In many instances the separation of a fluid mixture can be accomplished most expediently by centrifuging it at very high speed. The forces generated by centrifugation cause the heavier constituents of the mixture to settle out or "sediment" in layers according to their respective densities. For any given mixture, the higher the centrifugation speed the less time will be required to achieve a desired degree of sedimentation.
In some instances, such as where it is desired to separate minute viruses such as rubella, or the concentration of immunoglobulines from urine, it is necessary to achieve centrifugation speeds of a magnitude which are presently attainable only by air driven centrifuges. Centrifuges of this type, such as disclosed in U.S. Pat. No. 3,958,753 issued to Durland et al., and assigned to Beckman Instruments, Inc., the assignee of the present invention, are capable of reaching speeds as high as 200,000 R.P.M. Speeds of this magnitude can be achieved, because the rotor of such a machine is supported and rotated on a cushion of air by pressurized air streams, thus eliminating to a large extent the effect of mechanical friction.
The energy possessed by a rotor driven in such a manner is considerable, and could present a hazard to an operator if he were exposed to it by opening the door to the rotor chamber. There is, accordingly, a need for means to prevent the user from opening the access door to the rotor chamber of such a centrifuge while the rotor is rotating.